Advertising expenses amortization period.

No definition available.

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- Definition

Represents the number of dealer operated automotive repair centers.

+ References

No definition available.

+ Details

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- Definition

Represents the number of franchised stores.

+ References

No definition available.

+ Details

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- Definition

Number of retread facilities

+ References

No definition available.

+ Details

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- Definition

Number of wholesale locations

+ References

No definition available.

+ Details

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- Definition

Significant Accounting Policies [Line Items]

+ References

No definition available.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Topic 230
-SubTopic 10
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of loss contingency liability expected to be resolved after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 460
-SubTopic 10
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-Paragraph 2
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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

No definition available.

+ Details

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Represents the number of stores.

+ References

No definition available.

+ Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-SubTopic 10
-Section 50
-Paragraph 2
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Significant Accounting Policies (Narrative) (Details)	3 Months Ended	12 Months Ended
Significant Accounting Policies (Narrative) (Details)	Dec. 29, 2018 USD ($)	Mar. 30, 2019 USD ($) state segment property store item	Mar. 31, 2018 USD ($)
Significant Accounting Policies [Line Items]
Company operated stores \| store		1,197
Franchised locations \| store		98
Number of wholesale locations \| property		8
Number of retread facilities \| property		3
Dealer-operated automotive repair centers \| store		2
Number of States in which Entity Operates \| state		28
Number of operating segments \| segment		1
Number of reporting units \| item		1
Advertising expenses amortization period		2 months
Impairment of intangible assets	$ 0
Property Lease Guarantee [Member]
Significant Accounting Policies [Line Items]
Maximum potential guarantee payments		$ 1,800,000
Liability for anticipated lease defaults		$ 0	$ 200,000
Stock Options [Member]
Significant Accounting Policies [Line Items]
Options award vesting period		4 years
Senior Management [Member] \| Restricted Stock [Member]
Significant Accounting Policies [Line Items]
Options award vesting period		3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Adoption of new accounting principle		$ 190,000,000
Maximum [Member] \| Stock Options [Member]
Significant Accounting Policies [Line Items]
Options award vesting period		4 years
Maximum [Member] \| Restricted Stock [Member]
Significant Accounting Policies [Line Items]
Options award vesting period		4 years
Minimum [Member]
Significant Accounting Policies [Line Items]
Adoption of new accounting principle		$ 165,000,000
Minimum [Member] \| Stock Options [Member]
Significant Accounting Policies [Line Items]
Options award vesting period		3 years
Minimum [Member] \| Restricted Stock [Member]
Significant Accounting Policies [Line Items]
Options award vesting period		3 years
Buildings and Improvements [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Useful lives		39 years
Buildings and Improvements [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Useful lives		10 years
Machinery, Fixtures And Equipment [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Useful lives		15 years
Machinery, Fixtures And Equipment [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Useful lives		3 years
Vehicles [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Useful lives		10 years
Vehicles [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Useful lives		5 years
Computer Hardware And Software [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Useful lives		7 years
Computer Hardware And Software [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Useful lives		3 years